Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754060Ab3H1PjU (ORCPT ); Wed, 28 Aug 2013 11:39:20 -0400 Received: from mx1.redhat.com ([209.132.183.28]:31916 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753960Ab3H1PjT (ORCPT ); Wed, 28 Aug 2013 11:39:19 -0400 Subject: [PATCH v3] i915: Update VGA arbiter support for newer devices To: intel-gfx@lists.freedesktop.org From: Alex Williamson Cc: airlied@redhat.com, linux-kernel@vger.kernel.org, ville.syrjala@linux.intel.com Date: Wed, 28 Aug 2013 09:39:08 -0600 Message-ID: <20130828153700.10255.67664.stgit@bling.home> User-Agent: StGit/0.16 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3959 Lines: 107 This is intended to add VGA arbiter support for Intel HD graphics on Core processors. The old GMCH registers no longer exist, so even though it appears that i915 participates in VGA arbitration, it doesn't work. On Intel HD graphics we already attempt to disable VGA regions of the device. This makes registering as a VGA client unnecessary since we don't intend to operate differently depending on how many VGA devices are present. We can disable VGA memory regions by clearing the memory enable bit in the VGA MSR. That only leaves VGA IO, which we update the VGA arbiter to know that we don't participate in VGA memory arbitration. We also add a hook on unload to re-enable memory and reinstate VGA memory arbitration. Signed-off-by: Alex Williamson --- v3: Use explicit LEGACY_IO | LEGACY_MEM when restoring rather than LEGACY_MASK, per Ville's comments. v2: I915_READ/WRITE accessors don't work in i915_disable_vga, use inb/outb directly. Also, on the driver unbind VGA enable path, acquire legacy IO to re-enable VGA memory. Correct comment. As with v1, this depends on "vgaarb: Fixes for partial VGA opt-out". With all patches I'm able to assign a discrete PEG VGA device to a guest and execute the VBIOS w/o interference from IGD or corruption of the IGD framebuffer. drivers/gpu/drm/i915/i915_dma.c | 9 ++++++--- drivers/gpu/drm/i915/intel_display.c | 25 +++++++++++++++++++++++++ 2 files changed, 31 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c index f466980..d9cf216 100644 --- a/drivers/gpu/drm/i915/i915_dma.c +++ b/drivers/gpu/drm/i915/i915_dma.c @@ -1287,9 +1287,12 @@ static int i915_load_modeset_init(struct drm_device *dev) * then we do not take part in VGA arbitration and the * vga_client_register() fails with -ENODEV. */ - ret = vga_client_register(dev->pdev, dev, NULL, i915_vga_set_decode); - if (ret && ret != -ENODEV) - goto out; + if (!HAS_PCH_SPLIT(dev)) { + ret = vga_client_register(dev->pdev, dev, NULL, + i915_vga_set_decode); + if (ret && ret != -ENODEV) + goto out; + } intel_register_dsm_handler(); diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 5fb3058..2807760 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -9519,6 +9519,15 @@ static void i915_disable_vga(struct drm_device *dev) outb(SR01, VGA_SR_INDEX); sr1 = inb(VGA_SR_DATA); outb(sr1 | 1<<5, VGA_SR_DATA); + + /* Disable VGA memory on Intel HD */ + if (HAS_PCH_SPLIT(dev)) { + outb(inb(VGA_MSR_READ) & ~VGA_MSR_MEM_EN, VGA_MSR_WRITE); + vga_set_legacy_decoding(dev->pdev, VGA_RSRC_LEGACY_IO | + VGA_RSRC_NORMAL_IO | + VGA_RSRC_NORMAL_MEM); + } + vga_put(dev->pdev, VGA_RSRC_LEGACY_IO); udelay(300); @@ -9526,6 +9535,20 @@ static void i915_disable_vga(struct drm_device *dev) POSTING_READ(vga_reg); } +static void i915_enable_vga(struct drm_device *dev) +{ + /* Enable VGA memory on Intel HD */ + if (HAS_PCH_SPLIT(dev)) { + vga_get_uninterruptible(dev->pdev, VGA_RSRC_LEGACY_IO); + outb(inb(VGA_MSR_READ) | VGA_MSR_MEM_EN, VGA_MSR_WRITE); + vga_set_legacy_decoding(dev->pdev, VGA_RSRC_LEGACY_IO | + VGA_RSRC_LEGACY_MEM | + VGA_RSRC_NORMAL_IO | + VGA_RSRC_NORMAL_MEM); + vga_put(dev->pdev, VGA_RSRC_LEGACY_IO); + } +} + void intel_modeset_init_hw(struct drm_device *dev) { intel_init_power_well(dev); @@ -9983,6 +10006,8 @@ void intel_modeset_cleanup(struct drm_device *dev) intel_disable_fbc(dev); + i915_enable_vga(dev); + intel_disable_gt_powersave(dev); ironlake_teardown_rc6(dev); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/